JAMB UTME - Biology - 2018
Pergunta 1 Relatório
The damage to ozone layer is caused by
Detalhes da Resposta
Ozone sits in the upper atmosphere and absorbs ultraviolet radiaton, another type of solar energy that's harmful to humans, animals and plants. CFCs and halons cause chemical reactions that break down ozone molecules, reducing ozone's ultraviolet radiation-absorbing capacity. Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion.
Pergunta 2 Relatório
The role of scolex in tapeworm is to
Detalhes da Resposta
An adult tapeworm consists of a knoblike head, or scolex, equipped with hooks for attaching to the intestinal wall of the host (which may be a human), a neck region, and a series of flat, rectangular body segments, or proglottids, generated by the neck. Scolex is used for attachment to the intestinal wall.
Pergunta 3 Relatório
The energy released by 1 gram of glucose is
Detalhes da Resposta
The energy released by 1 gram of glucose is about 4 kcal. To put it simply, when our bodies break down glucose, a type of sugar that is a source of energy, it releases energy that we can use. This energy is measured in units of calories, and 1 kilocalorie (kcal) is equivalent to 1,000 calories. So, when 1 gram of glucose is broken down, it releases approximately 4 kcal of energy.
Pergunta 4 Relatório
Evidence of evolution include the following except
Detalhes da Resposta
Note: Evolution is a process of gradual change that takes place over many generations, during which species of animals, plants, or insects slowly change some of their physical characteristics.
Pergunta 5 Relatório
Use the diagram shown to answer the question. The experiment above is used to demonstrate the process of
Detalhes da Resposta
The experiment shown in the diagram is used to demonstrate the process of osmosis. Osmosis is the movement of water molecules across a selectively permeable membrane from an area of high water concentration to an area of low water concentration. In the experiment, the selectively permeable membrane is the potato cell membrane, and the water moves from the area of high concentration (in the beaker) to the area of low concentration (inside the potato). This causes the potato to swell and become heavier as it absorbs the water through osmosis. Thus, the experiment demonstrates the process of osmosis.
Pergunta 6 Relatório
A seed of a flowering plant can best be described as
Detalhes da Resposta
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth with in the motherplant.
Pergunta 7 Relatório
The reason why hospitals use saline solutions as drip instead of water is
Detalhes da Resposta
Saline, also known as saline solution, is a mixture of sodium chloride in water and has a number of uses in medicine. Intravenous therapy (IV) is a therapy that delivers liquid substances directly into a vein. Saline is used in I.V. therapy, intravenously supplying extra water to rehydrate patients or supplying the daily water and salt needs ("maintenance" needs) of a patient who is unable to take them by mouth. Because infusing a solution of low osmolality can cause problems such as hemolysis, intravenous solutions with reduced saline concentrations typically have dextrose (glucose) added to maintain a safe osmolality while providing less sodium chloride. The amount of normal saline infused depends largely on the needs of the patient (e.g. ongoing diarrhea or heart failure).
Pergunta 8 Relatório
The curvature movement of plants in response to the stimulus of water is called
Detalhes da Resposta
The curvature movement of plants in response to the stimulus of water is called "hydrotropism." Hydrotropism is a type of plant movement that occurs when a plant's roots grow towards a source of water. This is an important mechanism that allows plants to find water and nutrients in the soil.
When a plant is exposed to a source of water, such as a moist patch of soil, the plant's roots will start to grow towards the water. This is because the cells on the side of the root closest to the water absorb more water and expand, causing the root to bend towards the source of water. As the root grows towards the water, it will continue to bend until it reaches the water source.
Hydrotropism is different from other types of plant movements, such as geotropism, phototropism, and thigmotropism, which involve responses to gravity, light, and touch, respectively.
Pergunta 9 Relatório
Use the diagram to answer the question. The diagram shows that the organisms are
Detalhes da Resposta
Pergunta 10 Relatório
Which of the following cycles involves the process of precipitation and transpiration?
Detalhes da Resposta
The cycle that involves the process of precipitation and transpiration is the water cycle.
The water cycle is the process by which water circulates through the Earth's environment. It starts with the evaporation of water from bodies of water, such as oceans, lakes, and rivers, as well as from the soil and plants through a process called transpiration. This water vapor then rises into the atmosphere, where it cools and condenses into clouds. When these clouds become heavy enough, the water falls back to Earth as precipitation, which can take the form of rain, snow, sleet, or hail.
Once the precipitation falls to the ground, it can either be absorbed by the soil and become groundwater or run off into bodies of water. From there, the cycle starts again.
In summary, the water cycle involves the process of precipitation, which is the falling of water from the atmosphere to the Earth's surface, as well as the process of transpiration, which is the release of water vapor from plants. This cycle is essential for providing fresh water to living things and maintaining the Earth's environment.
Pergunta 11 Relatório
A beaker of pond water containing few specimens of Euglena was placed in a dark room for two weeks. At the end of this period, the specimens of Euglena were still alive because they were
Detalhes da Resposta
Holozoic nutrition is a type of heterotrophic nutrition that is characterized by the internalization (ingestion) and internal processing of gaseous, liquid or solid food particles. Protozoa, such as amoebas, and most of the free living animals,such as animals, exhibit this type of nutrition.
In holozoic nutrition the energy and organic building blocks are obtained by ingesting and then digesting other organisms or pieces of other organisms, including blood and decaying organic matter. This contrasts with holophytic nutrition, in which energy and organic building blocks are obtained through photosynthesis or chemosynthesis, and with saprozoic nutrition, in which digestive enzymes are released externally and the resulting monomers (small organic molecules) are absorbed directly from the environment.
Holophytic (plant-like), holozoic (animal- like), and saprophytic nutrition is found in Euglena. Euglena obtains its carbohydrate food by photosynthesis and nitrogenous food by absorption from the surroundings. Its holozoic nutrition is, however, doubtful.
In holozoic nutrition the energy and organic building blocks are obtained by ingesting and then digesting other organisms or pieces of other organisms, including blood and decaying organic matter. This contrasts with holophytic nutrition, in which energy and organic building blocks are obtained through photosynthesis or chemosynthesis, and with saprozoic nutrition, in which digestive enzymes are released externally and the resulting monomers (small organic molecules) are absorbed directly from the environment.
Holophytic (plant-like), holozoic (animal- like), and saprophytic nutrition is found in Euglena. Euglena obtains its carbohydrate food by photosynthesis and nitrogenous food by absorption from the surroundings. Its holozoic nutrition is, however, doubtful.
Pergunta 12 Relatório
Long neck in giraffe is used to illustrate the theory of
Detalhes da Resposta
The giraffe's long neck is a perfect adaptation to the animal's natural habitat. Clearly the giraffe evolved this uncommon and helpful trait in order to reach those nourishing leaves. That's how natural selection works. Use and disuse' theory in human life advocate the idea that animals acquired characteristics after using certain physical traits constantly.
Pergunta 13 Relatório
Cold blooded animals are referred to as
Detalhes da Resposta
Cold-blooded animals are referred to as "poikilothermic".
Poikilothermic animals are also known as "ectothermic" animals, which means that their body temperature is regulated by the environment around them. This is in contrast to "homoeothermic" animals, also known as "endothermic" animals, which can regulate their own body temperature internally.
Examples of poikilothermic animals include reptiles, amphibians, and most fish. These animals are often seen basking in the sun to warm up or seeking out cooler places in order to lower their body temperature. They are able to function at a range of different temperatures, but their bodily functions are often slower at cooler temperatures.
On the other hand, homoeothermic animals, such as mammals and birds, are able to maintain a stable internal body temperature, even when the temperature of their environment fluctuates. This allows them to function effectively in a wider range of environmental conditions.
Pergunta 14 Relatório
Ozone hole refers to
Detalhes da Resposta
Chlorofluorocarbons (CFCs) and other halogenated ozone depleting substances (ODS) are mainly responsible for man-made chemical ozone depletion.
Pergunta 15 Relatório
Examples of micronutrients include the following except
Detalhes da Resposta
The essential elements can be divided into macronutrients and micronutrients. Nutrients that plants require in larger amounts are called macronutrients. About half of the essential elements are considered macronutrients: carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur.
Pergunta 16 Relatório
Which of the following is a mixed gland?
Detalhes da Resposta
A mixed gland is a gland that is both exocrine and endocrine, for example, the pancreas. Pancreas is known as a mixed gland because it performs functions of both exocrine and endocrine glands.
Pergunta 17 Relatório
The process in which plant uses sunlight to synthesize nutrients from carbon dioxide and water is called
Detalhes da Resposta
The process in which plants use sunlight to synthesize nutrients from carbon dioxide and water is called photosynthesis. Photosynthesis is a crucial process that enables plants to produce their own food and is responsible for releasing oxygen into the atmosphere. During photosynthesis, plants use chlorophyll, a pigment found in their leaves and other green parts, to capture energy from sunlight. This energy is used to combine carbon dioxide and water to produce glucose (a type of sugar) and oxygen. The glucose produced is then used by the plant as an energy source to fuel its growth and other metabolic processes. In summary, photosynthesis is the process by which plants convert sunlight into chemical energy, which they use to synthesize nutrients and sustain their growth and survival.
Pergunta 18 Relatório
DNA in eukaryotic cells is contained in the
Detalhes da Resposta
DNA in eukaryotic cells is contained in the nucleus. The nucleus is a membrane-bound structure found in eukaryotic cells that acts as the "brain" of the cell, controlling and regulating all of its functions. It is also where the cell's DNA is stored and protected, in a substance called chromatin. The DNA in the chromatin is organized into long structures called chromosomes, which are visible during cell division. In short, the nucleus is the place where the DNA of a eukaryotic cell is located and it plays a vital role in the functioning of the cell.
Pergunta 19 Relatório
Which of the following features is not a characteristic of arteries? Arteries
Detalhes da Resposta
The arteries are the blood vessels that deliver oxygen-rich blood from the heart to the tissues of the body. Each artery is a muscular tube lined by smooth tissue and has three layers: The intima, the inner layer lined by a smooth tissue called endothelium. Arteries have smaller lumens than veins, a characteristic that helps to maintain the pressure of blood moving through the system. They carry blood away from the heart. Pulmonary arteries transport blood that has a low oxygen content from the right ventricle to the lungs. Arteries do not possess valves at intervals throughout their length
Pergunta 20 Relatório
The flippers of a whale and the fins of a fish are examples of
Detalhes da Resposta
The flippers of a whale and the fins of a fish are examples of convergent evolution.
Convergent evolution is a process where species that are not closely related, but live in similar environments, evolve similar structures or adaptations to solve similar problems. This is also known as "parallel evolution".
For example, whales and fish both live in water, and both need to be able to swim and maneuver. Over time, both species have evolved flippers or fins as a solution to these challenges, even though whales are mammals and fish are fish. This convergence of similar structures in unrelated species is a result of convergent evolution.
Pergunta 21 Relatório
The hygrometer is used for measuring
Detalhes da Resposta
A hygrometer is an instrument used to measure the amount of humidity and water vapor in the atmosphere, in soil, or in confined spaces. Humidity measurement instruments usually rely on measurements of some other quantity such as temperature, pressure, mass, a mechanical or electrical change in a substance as moisture is absorbed. By calibration and calculation, these measured quantities can lead to a measurement of humidity.
Pergunta 22 Relatório
Which of the following diseases is not hereditary?
Detalhes da Resposta
Scabies is the disease that is not hereditary.
Scabies is a skin infestation caused by a tiny mite called Sarcoptes scabiei. It spreads through direct skin-to-skin contact with an infected person. Scabies is not a genetic disorder and does not pass down from parent to child through genes. It is caused by a microscopic organism that can infect anyone who comes into contact with it.
On the other hand, Albinism, Haemophilia, and Color blindness are all hereditary diseases. Albinism is a genetic condition that affects the production of melanin, resulting in little or no pigment in the skin, hair, and eyes. Haemophilia is a genetic disorder that affects the blood's ability to clot properly. Color blindness is a genetic condition that affects the ability to distinguish between different colors.
In summary, while Scabies is caused by a tiny mite and is not hereditary, Albinism, Haemophilia, and Color blindness are all genetic conditions that are inherited from one's parents.
Pergunta 23 Relatório
A pollutant that is mostly associated with acid rain is
Detalhes da Resposta
The pollutant that is mostly associated with acid rain is nitrogen (IV) oxide, also known as nitrogen dioxide (NO2).
NO2 is produced when fuels such as coal, oil, and gas are burned at high temperatures, particularly in vehicles and power plants. It is a gas that can react with other chemicals in the atmosphere to form nitric acid (HNO3), which can then fall to the ground as acid rain.
When acid rain falls on soil, it can lower the pH and make it more acidic. This can have negative effects on plants and animals that live in the soil, as well as on the quality of the water in lakes and streams. In addition, acid rain can corrode buildings and other structures made of stone, metal, or concrete.
To reduce the production of nitrogen (IV) oxide and the formation of acid rain, it is important to reduce the use of fossil fuels and to use cleaner sources of energy, such as wind, solar, and hydropower. Additionally, regulations and policies can be put in place to limit the emissions of nitrogen (IV) oxide from vehicles and power plants.
Pergunta 24 Relatório
An organism which exhibit extracellular digestion is
Detalhes da Resposta
Extracellular digestion is a process in which saprobionts feed by secreting enzymes through the cell membrane onto the food. During extracellular digestion, food is broken down outside the cell either mechanically or with acid by special molecules called enzymes.
Pergunta 25 Relatório
A man who is heterozygous for the disease haemophilia marries a woman who is double recessive for haemophilia. What percentage of their offspring would have the disease?
Detalhes da Resposta
Haemophilia is an X-linked recessive genetic disorder. This means that the gene responsible for haemophilia is located on the X chromosome, and individuals with two copies of the defective gene (one inherited from each parent) will have the disease.
The man in this scenario is heterozygous, meaning he has one normal X chromosome and one X chromosome with the defective gene. The woman is double recessive, meaning she has two copies of the defective gene.
When the man and woman have offspring, each child will inherit one of their father's X chromosomes and one of their mother's X chromosomes.
The possible combinations of X chromosomes the children could inherit are:
- Normal X chromosome from the father and normal X chromosome from the mother
- Normal X chromosome from the father and defective X chromosome from the mother
- Defective X chromosome from the father and normal X chromosome from the mother
- Defective X chromosome from the father and defective X chromosome from the mother
Of these possible combinations, only the last one (defective X chromosome from both parents) will result in the child having haemophilia.
The probability of a child inheriting a defective X chromosome from the father is 50%, since the father is heterozygous. The probability of a child inheriting a defective X chromosome from the mother is 100%, since the mother is double recessive.
Therefore, the probability of a child inheriting a defective X chromosome from both parents and having haemophilia is 50% x 100% = 50%.
So the correct answer is: 50% of their offspring would have the disease.
Pergunta 26 Relatório
A group of closely related organisms capable of interbreeding to produce the fertile offspring are known as members of a
Detalhes da Resposta
The correct answer is "species".
Species are a group of living organisms that share common characteristics and can interbreed to produce fertile offspring. This means that members of the same species can mate and produce offspring that can themselves reproduce, while organisms from different species cannot produce fertile offspring together.
For example, dogs can breed with other dogs to produce fertile puppies, but they cannot breed with cats to produce offspring that can reproduce. Therefore, dogs and cats belong to different species.
Pergunta 27 Relatório
Spectacles with convex lenses correct long-sightedness by
Detalhes da Resposta
Spectacles with convex lenses correct long-sightedness by converging the light rays before they enter the eye.
In long-sightedness, also known as hyperopia, the eyeball is too short, which causes light to focus behind the retina instead of directly on it. This results in blurry vision, especially when looking at close objects.
Convex lenses are thicker in the middle and thinner at the edges, and they bend light rays towards each other. When a person with long-sightedness wears spectacles with convex lenses, the lenses converge the light rays before they enter the eye, which compensates for the shortness of the eyeball. This causes the light rays to focus directly on the retina, which results in clearer vision.
Therefore, by converging the light rays before they enter the eye, convex lenses correct long-sightedness.
Pergunta 28 Relatório
A distinguishing feature of mammals is the possession of
Detalhes da Resposta
One distinguishing feature of mammals is the possession of hair. Hair is a unique type of structure that grows from the skin of mammals and is made up of a protein called keratin. Hair serves many important functions in mammals, such as keeping the body warm, protecting the skin from damage, and providing sensory information. Hair can also be used for social communication, such as when a cat raises its fur to make itself look bigger and more intimidating. While other animals like reptiles may have scales, and birds may have feathers, only mammals have hair as a defining feature.
Pergunta 29 Relatório
Which of the following groups of organisms has kidney as the excretory organ?
Detalhes da Resposta
The group of organisms that have kidneys as the excretory organ is: fishes, amphibians, birds, and man.
Kidneys are specialized organs that remove waste products, excess water, and other impurities from the blood. These waste products are then eliminated from the body as urine.
Fishes, amphibians, birds, and mammals (including humans) all have kidneys as their primary excretory organ. In fish, the kidneys are responsible for removing excess water and electrolytes from the blood. In amphibians, the kidneys also play a role in maintaining water balance, as well as removing nitrogenous wastes. In birds and mammals, the kidneys are responsible for filtering the blood, regulating water and electrolyte balance, and eliminating waste products.
In contrast, annelids (a group of segmented worms), insects, protozoans, reptiles, and tapeworms have different excretory organs. For example, insects have specialized structures called Malpighian tubules that remove waste products and excess water from their blood, while tapeworms excrete waste products through their skin.
Pergunta 30 Relatório
The cytoplasm of a cell is considered a very important component because it
Detalhes da Resposta
The jelly-like fluid that fills a cell is called cytoplasm. It is made up of mostly water and salt. Cytoplasm is present within the cell membrane of all cell types and contains all organelles and cell parts. Cytoplasm has various functions in the cell.
Most of the important activities of the cell occur in the cytoplasm. Cytoplasm contains molecules such as enzymes which are responsible for breaking down waste and also aid in metabolic activity.
Most of the important activities of the cell occur in the cytoplasm. Cytoplasm contains molecules such as enzymes which are responsible for breaking down waste and also aid in metabolic activity.
Pergunta 31 Relatório
What is the function of contractile vacuole in paramecium?
Detalhes da Resposta
The contractile vacuole in paramecium functions to get rid of excess water. Paramecium is a single-celled organism that lives in freshwater environments. As water enters the cell by osmosis, the contractile vacuole collects and pumps out the excess water to prevent the cell from swelling and potentially bursting. The contractile vacuole acts like a pump, contracting and releasing to expel the excess water out of the cell. This process helps maintain the proper balance of water and ions inside the cell, which is necessary for the organism's survival. Therefore, the function of the contractile vacuole in paramecium is to regulate water balance and prevent the cell from bursting due to excess water intake.
Pergunta 32 Relatório
Blood circulation in a mammal is said to be double because
Detalhes da Resposta
The majority of mammals (including humans) utilize a double circulatory system. This means we have two loops in our body in which blood circulates. One is oxygenated, meaning oxygen rich, and the other is deoxygenated, which means it has little to no oxygen, but a lot of carbon dioxide.
Pergunta 33 Relatório
Tikka disease is related with the crop
Detalhes da Resposta
Tikka disease is not related to the crop of Groundnut, Mustard, or Paddy.
Tikka disease, also known as Ascochyta blight, is a fungal disease that affects various plants, including beans, chickpeas, and lentils. The disease is caused by a fungus called Ascochyta and can result in small, circular spots on leaves, stems, and pods of infected plants. These spots can be gray, brown, or black, and may have a dark border.
In summary, Tikka disease is not related to the crops of Groundnut, Mustard, or Paddy. It affects plants such as beans, chickpeas, and lentils, and is caused by a fungus called Ascochyta.
Pergunta 34 Relatório
Which of the following instruments is used to estimate the number of plants in a habitat?
Detalhes da Resposta
The instrument used to estimate the number of plants in a habitat is a quadrant.
A quadrant is a square or rectangular frame that is used to isolate a specific area within a habitat for study. It is typically made of a lightweight and durable material, such as metal or plastic, and can be any size, depending on the needs of the study.
To estimate the number of plants in a habitat using a quadrant, researchers randomly select several quadrants within the study area and place them on the ground. They then count the number of plants within the quadrant and use this information to estimate the number of plants in the entire study area.
Quadrants are a commonly used tool in ecology and are particularly useful for estimating the density and distribution of plant populations. They are simple to use and can provide valuable information for researchers who are interested in understanding the dynamics of plant communities.
Pergunta 35 Relatório
How many days does it take for incubation of an egg to release chick?
Detalhes da Resposta
The incubation period for chicken eggs is generally 21 days. This means that after a fertilized egg is laid by a hen and is kept at the appropriate temperature and humidity in an incubator, it will take approximately 21 days for the chick to develop and hatch out of the eggshell.
During this period, the egg goes through several stages of development. In the first week, the embryo's circulatory system, nervous system, and digestive system start to form. In the second week, the chick's beak, wings, and claws begin to develop. And in the third week, the chick grows rapidly and prepares to break through the shell using its egg tooth, a small point on its beak.
It's important to note that the incubation period can vary slightly depending on factors such as the breed of chicken and the temperature and humidity in the incubator. However, 21 days is the average incubation period for chicken eggs.
Pergunta 36 Relatório
Study the diagram of a food chain shown and use it to answer the question.
P ---> Q ---> R ---> S ---> T
Which of the following statements best describes the organism designated R? It
Detalhes da Resposta
Primary consumers eat these plants exclusively and are all herbivores. We defined secondary consumers as organisms, primarily animals, which eat primary consumers. Furthermore, secondary consumers can be classified into one of two groups: carnivores, or meat eaters, and omnivores, which are plant and meat eaters.
Pergunta 37 Relatório
An animal which is active during the day is known as a
Detalhes da Resposta
An animal that is active during the day is known as a diurnal animal. This means that it is awake and active during the daytime hours, when the sun is shining, and typically sleeps or rests during the night. Diurnal animals have evolved to take advantage of the sunlight and are often adapted to see well in bright light. Examples of diurnal animals include humans, birds, squirrels, and many species of primates.
Pergunta 38 Relatório
An example of a radially symmetrical organisms is
Detalhes da Resposta
An example of a radially symmetrical organism is Hydra. Radial symmetry means that an organism has a circular shape and its body parts are arranged around a central axis, like the spokes on a wheel. Hydra is a small, freshwater animal that has a cylindrical body and tentacles that radiate out from its central axis. This type of symmetry allows Hydra to detect and capture prey from all directions. Planaria are also radially symmetrical flatworms, while tapeworms and roundworms are examples of organisms with bilateral symmetry, meaning that they have a distinct front and back and a left and right side.
Pergunta 39 Relatório
Etiolation is causes by the influence of
Detalhes da Resposta
Etiolation is caused by the influence of LIGHT.
Etiolation refers to the physical changes that occur in a plant when it is grown in the absence of sufficient light. When a plant does not receive enough light, it elongates its stem and leaves to reach for the light source. This results in a spindly, pale appearance, as the plant allocates its resources towards vertical growth rather than producing chlorophyll and other pigments needed for photosynthesis.
Therefore, the absence of light, or insufficient light, is the primary cause of etiolation. While mineral salts, water, and carbon dioxide are all necessary for plant growth, they do not directly cause etiolation.
Pergunta 40 Relatório
Name the blood cells in which nucleus is absent
Detalhes da Resposta
Like red cells, platelets (thrombocytes) have no nucleus. However, unlike red cells that originate in the marrow as nucleated cells and lose their nucleus, platelets are produced by budding off from a giant multinucleated marrow cell called a megakaryocyte.
